Advancements in communication technologies have permitted significant improvements in the manners by which data can be communicated between a sending and a receiving station.
For instance, in radio communications, advancements in digital communication techniques has permitted the introduction of, and popularization of, new types of communication systems. For example, cellular communication systems which utilize digital communication technologies have been installed in many areas and are widely utilized.
Advancements in communication technologies have also facilitated the decentralization of computer systems. Processing devices can be distributed at separate locations and connected together by network connections. Network connections between distributed processing devices and communications therebetween have precipitated, for instance, the advent of and wide availability of IP networks, such as the Internet. Other private data communication networks have similarly been formed.
The advancements in communication technologies have also permitted the merging of radio and network-connected communication systems. For instance, it is possible for a terminal device, such as a portable computer, to be coupled by way of a radio link to network infrastructure of a radio communication system and, in turn, by way of a network connection to an Internet-connected, network device. The terminal device forms a wireless host to the Internet-connected network device as a physical, such as a hard-wired, link is not formed with the terminal device.
A private IP network is formed of a group of network devices, connected together by way of network connections, but to which access to the network is limited. Increasing numbers of private IP networks are being created and access thereto by a wireless host is increasingly demanded. Increasing numbers of other data communication networks are being created and access thereto by a wireless host is increasingly demanded.
Because of the limited-access nature of a private network, there is a need to insure that the wireless host is authorized to access the private network. And, if the wireless host is authorized to access the private network, there is a corresponding need to insure that the wireless host properly receives an acceptable level of access to the private network. That is to say, the wireless host should be treated as a virtual host, given the level of access to the private network as that given to a host physically coupled to such network.
Because the coupling of a wireless host to a network device of a private data communication network includes a radio link, the wireless host must be identified by an address so that data can be communicated thereto. In some existing communication systems in which a wireless host is able to communicate with a network device, the address of the wireless host is dynamically allocated. That is to say, e.g., in an embodiment in which the private data communication network is formed of a private IP network, rather than assigning a permanent IP address to the wireless host, a temporary IP address is assigned to the host when data is to be communicated to the wireless host. IPv6 dynamic IP address allocation is exemplary of an allocation method by which dynamically to allocate IP addresses to wireless hosts. In such method, to provide a fixed identity for the wireless host, a DNS (Domain Name System) name is allocated. A DNS name is a symbolic name provided for wireless hosts and other devices connected to an IP network.
One manner by which a wireless host can access a private IP network is to utilize a dial-out connection from the wireless host to the private IP network. Once a switched connection is formed, the wireless host is identified with a password.
Another manner by which a wireless host is sometimes able to access the private IP network is through the use of an authenticated tunnel. The wireless host is connected to the private IP network by way of the authenticated tunnel, and the wireless host is authenticated at the private IP network with an identity and a password. Such a tunneling method is sometimes referred to as "layer two tunneling." A PPTP system developed by MicroSoft Corporation, an L2F system developed by Sysco Systems, and an L2TP system developed by IETF are related to tunneling PPP.
The existing manners by which a wireless host accesses a private IP, or other data communication, network requires significant amounts of protocol overhead. As in any bandwidth-limited communication system, protocol overhead is width-consumptive.
When the wireless host accesses the private network by way of the network infrastructure of a cellular communication system, portions of the network infrastructure function as a wireless access network. When, e.g., the private data communication network forms a private IP network, two IP addresses are required to permit communications between the wireless host and the private IP network. A first IP address is required at the wireless access network formed of the portion of the network infrastructure, and a second IP address is required at the private IP network. Thereby, the wireless host is required to belong to two networks, i.e., the access IP network and the private IP network.
As a result, two IP addresses must be allocated to the wireless host. If DNS is used in the two networks, it would also be necessary to allocate DNS names in both networks.
The layer two tunneling method requires formation of a protocol stack having three extra layers, the PPP layer, a layer two tunneling layer, and a basic IP layer. The protocol overhead resulting from such additional protocol layers is bandwidth-consumptive. Such a requirement is generally undesirable in a bandwidth-limited system.
Some wireless hosts are additionally capable of communicating packet data by way of circuit-switched as well as packet-switched connections. A GSM (Global System for Mobile communications) cellular communication system is exemplary of a cellular communication system which permits wireless hosts operable therein to communicate packet data by way of packet-switched and also circuit-switched connections. It would be advantageous to provide a manner by which to permit access of the wireless host to a private IP, or other data communication, network using the same access procedure irrespective of the type of data which is to be communicated therebetween.
In conventional manners by which to provide access of a wireless host to, e.g., a private IP network, dial-up connections are made directly to the private IP network. That connection may be made, for instance, to a remote access server of the private IP network. Telephonic charges associated with the dial-up connection can be significant. For instance, a long-distance toll might be charged to form the dial-up connection if an inter-LATA switched connection, or the like, is required between the network infrastructure of the cellular communication system and the private IP network. It would, of course, be desirable for the wireless host instead to be able to access a wireless access network as close as possible to the location at which the wireless host is positioned and thereafter to utilize IP transmission between the wireless access network and the private IP network.
A manner by which better to permit access of a wireless host to access a private data communication network to communicate packet data therebetween would be advantageous.
It is in light of this background information related to access of a wireless host and to a private IP network that the significant improvements of the present invention have evolved.